1. Field of the Invention
The present invention relates in general to printing systems and in particular to an ink well assembly for pad printing machines.
2. Related Art
Transfer pad printing machines or tampon printing machines have been used for many years for placing decorative markings, such as text and/or designs, on the surfaces of parts with a special ink. The special ink contains adhesive agents and typically dries as a hardened epoxy. This ensures proper adhesion of the ink to the printed surface and also promotes longevity of the decorative marking.
Transfer pad printing is extremely useful and versatile because it can be used to print desired images onto many types of substrate surfaces, such as wood, plastic, glass, metal, fabric, paper, etc. Also, desired images can be printed on numerous surface shapes, such as flat, round, curved, angled, or recessed surfaces, with transfer pad printing. Further, the desired images can be printed on these surfaces in multicolor, wet-on-wet inkings, without drying between colors. Some transfer pad printing applications include printing on automotive and electronic parts and outdoor recreational equipment, producing cosmetic color coding, producing point-of-purchase retail advertising and incentive and promotional material, etc.
A transfer pad printing machine typically includes a printing pad, an image plate having an image engraved thereon, and an ink well having ink located in a reservoir. The image plate is coupled to the ink well for providing ink in the engraved areas of the plate. Current ink wells are usually comprised of mating parts that are connected with fasteners and wedges that secure the image plate within the ink well. These ink wells typically require the use of caulking and silicone sealant around exposed wedges to seal and secure the image plate within the ink well. The wedges are used to move the image plate within an image plate holding area. The caulking and silicone sealant is used to limit the leaking of the ink. Ink is first flooded across the surface of the image plate and then excess ink is cleared from the non-engraved areas of the plate with a special blade, thereby leaving ink in only the engraved area. Next, the printing pad contacts the image plate in the engraved area and then contacts the surface of the substrate, thereby transferring the ink to the surface of the substrate to create a printed recreation of the desired image on the substrate.
However, current ink wells used in printing machines are lacking in several areas. For instance, current ink wells are expensive to make, maintain, and clean, which causes significant machine downtime. This is because current ink wells have numerous parts and are assembled with numerous fasteners, wedges, and sealants. The fasteners, wedges, and sealants are completely exposed to the ink, Since the ink typically used for pad printing machines dries as a hardened epoxy, current ink wells must be completely disassembled and cleaned by chiseling and scraping the ink from the ink well. As a result, the fasteners and wedges are regularly bent, disfigured, and/or damaged during chiseling and scraping of the ink and the sealant must be removed and reapplied after each use. Also, the fasteners, wedges, and sealants usually contain excessive build-up of ink, and thus require frequent replacement. These problems cause the use of additional labor and materials and create wasted downtime.
In addition, since current ink wells must be completely disassembled and cleaned after each ink change, these ink wells have a tendency to leak during reuse, after the ink wells are reassembled. This is caused by poor seals of mating parts and improper fitting of the fasteners, wedges, and sealants due to excessive ink build-up on exposed areas. Because the ink typically used for pad printing machines dries as a hardened epoxy, the hardened epoxy usually causes gaps and cracks around the wedges and the mating parts using the exposed fasteners to connect the parts. Consequently, the gaps and cracks cause the ink to leak around the wedges, the exposed fasteners, and mating parts.
Therefore, what is needed is a new ink well assembly that is easy to set up, clean, and incorporate with a pad printing machine without significant machine downtime. What is also needed is a new ink well assembly that is inexpensive and requires less parts. What is additionally needed is a new ink well assembly that doesn't leak ink. What is further needed is a new ink well assembly that does not require caulking, silicone adhesives, or wedges to seal or secure the image plate.
Whatever the merits of the above mentioned systems and methods, they do not achieve the benefits of the present invention.